Thomas, is there any chance that you have postfix installed in the environment where you're seeing the resolvconf job fail at boot? If so, this postfix resolvconf hook script probably explains what you're seeing. (And if you don't have postfix installed, it could be a different hook script causing a similar problem.)
Thomas, is there any chance that you have postfix installed in the environment where you're seeing the resolvconf job fail at boot? If so, this postfix resolvconf hook script probably explains what you're seeing. (And if you don't have postfix installed, it could be a different hook script causing a similar problem.)